The present invention relates to an information playback apparatus for reading out and playing back information recorded in an information recording medium, such as a DVD (Digital Versatile Disc), a CD (Compact Disc), and an MD (Mini Disc).
The present application claims priority from Japanese Application No.2001-281629, the disclosure of which is incorporated herein by reference for all purposes.
Recently, attention is being given to a DVD as an example of a large-capacity information recording medium capable of recording contents, such as long-playing movies and music. Also, an information playback apparatus for reading out and playing back information from the DVD is furnished with multiple functions to enhance the convenience of the user or the like, and for example, there is known a type furnished with a function called xe2x80x9cscan playback.xe2x80x9d
When the user or the like selects the scan playback, the information playback apparatus starts partial playback of the contents (referred to as titles in the case of a DVD), such as a movie recorded in the DVD, by jumping from one portion to another instead of performing continuous playback.
Hence, when the user or the like selects the scan playback, as schematically shown in a block (a) of FIG. 11, data in some portions of a movie or the like is skipped, and as shown in a block (b) of FIG. 11, partial playback is performed by playing back only the data in the remaining portions by jumping from one portion to another, which offers an advantage that the user or the like can have an overview of the movie or the like in a short time.
Incidentally, according the conventional scan playback, when a DVD is played, for example, skipping and partial playback are performed on the basis of a chapter unit or a track unit preset by a producer of the DVD or the like. In other words, because titles, such as a movie, are made up of a set of one or more chapters or tracks, a time length of the skip portions and a time length of partial playback portions are determined in such a manner that they are always natural number times the length of the chapter unit or the track unit.
Hence, there are problems that it is impossible to perform skipping and partial playback in units divided into a shorter time than the chapter unit or the track unit, and further, it is impossible to perform skipping and partial playback for a time length other than natural number times the length of the chapter unit or the tack unit.
To be more concrete, there is a problem as follows. That is, when the pre-set chapter unit or track unit is long, so are the respective skip portions illustrated in the block (a) of FIG. 11 by way of example. Hence, when the scan playback is performed as shown in the block (b) of FIG. 11, since the skip portions are too long, much of the story is missing between the respective playback portions #1 though #n, which poses a problem that the user or the like cannot readily follow the plot from the videos derived from the scan playback.
Also, as illustrated in a block (c) of FIG. 11 by way of example, when all the titles, such as a movie, are recorded in a single chapter, there is a problem that the user or the like cannot practically use the conventional scan playback. In such a case, when the scan playback is performed, no skipping is performed as shown in a block (d) of FIG. 11, and a movie or the like is played from beginning to end as a playback portion. As a result, there is a problem that the substantial advantage of the scan playback cannot be attained.
The present invention has been devised to solve the above conventional problems, and therefore, has an object to provide a more convenient information playback apparatus capable of, for example, setting finer playback portion and skip portion than a chapter unit or a track unit.
In order to achieve the above and other objects, an information playback apparatus of the present invention is an information playback apparatus for playing back playback data recorded in an information recording medium as a set of data in predetermined smallest basic units, including: playback device for playing back playback control data including address information and information of a playback order of all the data in the smallest basic units and recorded in the information recording medium to perform playback control of the playback data, and for playing back the playback data according to the playback control data; and control device for, upon being specified by a playback time for every unit cycle, setting the playback time for every unit cycle as desired playback times to perform playback of the playback data and managing the desired playback times according to the address information, and for controlling the playback device to playback, of all the data in the smallest basic units, only the data corresponding to the desired playback times.
According to the information playback apparatus of the present invention arranged as above, when the user or the like specifies the playback time for every unit cycle, the playback data is divided into unit cycles, and a playback time within each divided unit cycle is set as a desired playback time. Then, of all the playback data, only the data corresponding to the desired playback times is played back based on the playback control data, whereby scan playback can be performed. When scan playback is performed for the playback data made up as a set of data in the smallest basic units, divided times by a unit time and the desired playback times are managed based on the address information of all the data in the smallest basic units, and only the data within the desired playback times is played back seamlessly. In this manner, by performing playback deeming the data in the smallest basic units (which are the basal elements of the playback data) as the subjects of playback, it is possible to realize accurate scan playback. Moreover, it is possible to set non-playback portions and playback portions of so-called titles accurately and freely.
Also, with the information playback apparatus of the present invention, after the data in the smallest basic units corresponding to one of the desired playback times is played back, and when access-inhibited data is present at a start position of a next desired playback time, the control device controls the playback device to continue to perform playback except said access-inhibited data.
According to the above arrangement, in a case where the access-inhibited data is contained in the playback data, after the data in the smallest basic units corresponding to one of the desired playback times defined by the unit cycles is played back and when scan playback is being performed and the access-inhibited data is present at the start position of a next desired playback time, playback is performed by omitting the access-inhibited data from the objects of playback. Consequently, for example, even when the access-inhibited data is set by an edit function of the information recording medium or the like, it is still possible to realize scan playback which does not go against the standard of information recording media by omitting the access-inhibited data from the objects of scan playback.
In addition, with the information playback apparatus of the present invention, when the access-inhibited data is present at the start position of the next desired playback time, the control device controls the playback device to omit the next desired playback time and then to continue to perform playback from a further next desired playback time.
According to the above arrangement, when the access-inhibited data is omitted, the unit cycle itself which contains the access-inhibited data is omitted, so that playback is continued from the next unit cycle, thereby realizing scan playback which does not go against the standard of the information recording media.